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Date: Wed, 3 Jan 2024 23:34:12 -0800
From: "Darrick J. Wong" <djwong@kernel.org>
To: Christoph Hellwig <hch@infradead.org>
Cc: linux-xfs@vger.kernel.org
Subject: Re: [PATCH 3/3] xfile: implement write caching
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On Wed, Jan 03, 2024 at 11:28:21PM -0800, Christoph Hellwig wrote:
> On Wed, Jan 03, 2024 at 11:20:50PM -0800, Darrick J. Wong wrote:
> > > Sure, I just suspect the commit message is wrong and it's not about
> > > mapping the page into the kernel address space but something else.
> > 
> > Yeah, I only did A/B testing of before and after this patch, so it's
> > quite plausible that it's the lookup that's slowing us down.
> 
> Can we re-rerun the test once the pending xfile changes are in?
> I'd be kinda surprised if the fairly simply xarray lookup for the
> page is so expensive.  If it is the patch is a good bandaid for that,
> I'd just like to ensure it actually is still needed.

Ok, I'll do that.  Were you planning to send that first series to
Chandan for 6.8?

--D